In the past, certain special services have been made available to telephone customers to provide them with features which render their telephone usage more convenient and more flexible. For example, these services include call screening, calling number identification, automatic recall and callback, customer-originated call tracing, and others in which special service information is sent to a selected station. This special service information may include a special service indication, the directory number of a called/calling station, personal messages, etc.
Historically, this special service information has been sent to an off-hook station in the form of audio messages from a telephone office announcement system. This is particularly annoying when the customer wants to screen calls prior to answering and respond to only designated parties. In addition, a customer may have initiated several special services at the same time in which the customer is rung back. When rung back, the customer wants to known the identity of the special service or associated party before responding to the ring back signal.
Another solution to providing the customer with special service information is to have a separate data communication link associated with the customer station. However, unless the data link is used with other data processing services, this is a very inefficient and costly approach.